The invention discloses an airlift internal loop slurry-bed reactor. The airlift internal loop slurry-bed reactor comprises a shell, a guide cylinder, a gas distributor, a gas-liquid separation apparatus, a bottom inlet, a top outlet and a slurry bed layer, the gas-liquid separation apparatus, the guide cylinder and the gas distributor are arranged in the shell from up to down in order, the annular space of the guide cylinder and the inner wall of the shell are filled with the slurry bed layer, and the guide cylinder comprises an upper baffling section and a lower straight-tube enclosing section. According to the invention, the upper part of the guide cylinder is designed as a baffling communication section, the gas-liquid separation effect of the reactor is increased, circulation of a slurry in the guide cylinder and the slurry out of the guide cylinder is promoted, so that the problems that when the operating gas velocity is high, the slurry back-mixing and mist entrainment are generated can be avoided, the reaction efficiency, purity of the products and the stability of a catalyst are indirectly increased, and the energy consumption and investment of the reactor are reduced.